The Montgomery ladder implementation in OpenSSL through 1.0.0l does not ensure that certain swap operations have a constant-time behavior, which makes it easier for local users to obtain ECDSA nonces via a FLUSH+RELOAD cache side-channel attack.
Exploitability
AV:LAC:MAu:NImpact
C:PI:NA:N1.9/AV:L/AC:M/Au:N/C:P/I:N/A:N